The invention relates to hydroforming and, more particularly, to the components used during the hydroforming process for forming bellows.
Several processes may be used for forming pieces of metal into bellows, such as hydroforming, roll forming and an elastomeric process. During hvdroforming, a plurality of dies are positioned parallel and adjacent to one another. A hollow tube is inserted within the dies and held in position by the dies. As water is forced through the hollow tube, the water pressure against the tube expands the wall of the tube outwardly. The dies apply pressure against the wall of the tube at the desired locations along the length of the tube so that the wall of the tube is only expanded between adjacent dies. The dies are compressed together for forcing the expanded sections of the wall into a corrugated pattern for forming bellows.
Currently, the die is formed from two separate die plates. The two die plates may be separated for inserting the tube into the die. After the tube is inserted into the die, the die plates are clamped together around the tube. Previously, the two die plates were hydraulically held together. Alternatively, the two die plates have been held together by cylindrical keys. However, the inadvertent rotation of one of the keys, due to the cylindrical design of the keys, may interfere with an adjacent key.
Each of the dies contained within the die housing is held in position with respect to one another by pins and links. To hold each pin in position within the die requires a mechanical means. Previously, a solid sheet of metal contacted and retained each pin. However, the use of a solid piece of metal which contacted the pins and extended across the open space between adjacent dies obstructed the view into the die and prohibited an operator of the machine from viewing the bellows making process.
Therefore, what Is needed is an apparatus for making bellows which utilizes components which reduce interference with other components and enable an operator to observe the tube positioned within the dies during the bellows making process.
A hydroforming machine includes a die housing, a water distribution system coupled to the die housing, and a plurality of dies contained within the die housing. Each of the dies has a first die plate and a second die plate which are mateably connectable The first die plate has a first keyway and the second die plate has a second keyway which are alignable with respect to one another. A key is insertable into the aligned first and second keyways of the first and second die plates. The key has an elongated end and a handle end. The elongated end is non-rotatable and insertable into the first and second keyways. The handle end extends from the first and second keyways for enabling manual and automatic manipulation of the key.
The hydroforming machine also includes the first die plate having a plurality of apertures and at least one pin disposed within the apertures of the dies. A keeper is disposed within an opening of the first die plate and contacts the pin for retaining the pin within the apertures. The keeper has an elongated portion sized approximately equivalent in width as the die for enabling observation into the die housing during the hydroforming process.